1. Technical Field
The present invention relates to maximum-transition-run (MTR) block codes for use in partial response maximum likelihood (PRML) based recording systems and particularly to a new class of PRML(G, I, M) codes which in addition to the global G-constraint and the interleaved I-constraint enforce a variable frequency oscillator (VFO) constraint also known as an M-constraint.
2. Description of the Related Art
In magnetic recording and optical storage, modulation constraints are employed on recorded binary sequences to facilitate timing recovery and ensure efficient operation of a detector. The large class of PRML(G, I) codes, which are based on even/odd interleaved generalized Fibonacci codes, satisfy G and I constraints but do not achieve the desired VFO constraint.